Lighting - Revision history

Michel Lamontagne: /* Agriculture */

2023-01-06T04:27:50Z

Agriculture

Michel Lamontagne: /* Agriculture */

2023-01-06T03:41:53Z

Agriculture

Michel Lamontagne: /* Agriculture */

2023-01-06T02:13:32Z

Agriculture

Michel Lamontagne: /* Agriculture */

2023-01-06T02:11:35Z

Agriculture

Michel Lamontagne: /* Agriculture */

2021-04-16T02:07:45Z

Agriculture

Michel Lamontagne at 16:28, 6 November 2020

2020-11-06T16:28:29Z

Michel Lamontagne: /* Agriculture */

2020-11-06T16:24:04Z

Agriculture

Michel Lamontagne at 02:39, 26 December 2019

2019-12-26T02:39:06Z

Michel Lamontagne at 04:01, 23 December 2019

2019-12-23T04:01:30Z

Michel Lamontagne: /* Incandescent */

2019-12-22T20:01:37Z

Incandescent

← Older revision		Revision as of 04:27, 6 January 2023
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	This can be compared to the [[Food\|crop yields]] obtained on Earth, that vary between 10 and 50 t/ha for high yield crops. So although Mars surface greenhouses can work, the yield might be lower and supplemental lighting required for higher crop yields.		This can be compared to the [[Food\|crop yields]] obtained on Earth, that vary between 10 and 50 t/ha for high yield crops. So although Mars surface greenhouses can work, the yield might be lower and supplemental lighting required for higher crop yields.
		+
		+	The use of [[hydroponics]] with artificial lighting and many layers of trays can increase yields in t/ha up to 600-2000 t/ha. https://www.freightfarms.com/

	==Lighting levels==		==Lighting levels==

@@ Line 36: / Line 36: @@
 Many plants require more sunlight than is available on the Martian surface. [[Dust storms]] can also obscure the sun for months at a time. Artificial lighting is needed to at least augment the natural light.
-Interior grow rooms use artificial light for plant production.  This technology was developed for the production of Cannabis in closed environments but is applicable to all indoor grown plants.  The most common power used for these installations is 300-600 W/m2 of lighting, or about one quarter to one half the power of full sunlight.
+Interior grow rooms use artificial light for plant production.  This technology was developed for the production of Cannabis in closed environments and container farming but is applicable to all indoor grown plants.  The most common power used for these installations is 300-600 W/m2 of lighting, or about one quarter to one half the power of full sunlight.
 Food production is a factor of the amount of illumination received by the plant.  A useful equation for a surface greenhouse is:

@@ Line 52: / Line 52: @@
 For 260 days of production per year the yield would be 1.7 kg/m2 per year, or about 17 t/ha.
-This can be compared to the [[Food|crop yields]] obtained on Earth, that vary between 20 and 100 t/ha for high yield crops.  So although Mars surface greenhouses can work, the yield might be relatively low and supplemental lighting required for higher crop yields.
+This can be compared to the [[Food|crop yields]] obtained on Earth, that vary between 10 and 50 t/ha for high yield crops.  So although Mars surface greenhouses can work, the yield might be lower and supplemental lighting required for higher crop yields.
 ==Lighting levels==

@@ Line 52: / Line 52: @@
 For 260 days of production per year the yield would be 1.7 kg/m2 per year, or about 17 t/ha.
-This can be compared to the [[Food|crop yields]] obtained on Earth, that vary between 3 and 400 t/ha for high yield crops.  So although Mars surface greenhouses can work, the yield might be relatively low and supplemental lighting required for higher crop yields.
+This can be compared to the [[Food|crop yields]] obtained on Earth, that vary between 20 and 100 t/ha for high yield crops.  So although Mars surface greenhouses can work, the yield might be relatively low and supplemental lighting required for higher crop yields.
 ==Lighting levels==

@@ Line 34: / Line 34: @@
 ===Agriculture===
-Many plants require more sunlight than is available on the martian surface. [[Dust storms]] can also obscure the sun for months at a time. Artificial lighting is needed to at least augment the natural light.
+Many plants require more sunlight than is available on the Martian surface. [[Dust storms]] can also obscure the sun for months at a time. Artificial lighting is needed to at least augment the natural light.
-Interior grow rooms use artificial light for plant production.  This technology was developed for the production of Cannabis in closed environments but is applicable to all indoor grown plants.  The most common power used for these installations is 300-600 W/m2, or about one quarter to one half the power of full sunlight.
+Interior grow rooms use artificial light for plant production.  This technology was developed for the production of Cannabis in closed environments but is applicable to all indoor grown plants.  The most common power used for these installations is 300-600 W/m2 of lighting, or about one quarter to one half the power of full sunlight.
 Food production is a factor of the amount of illumination received by the plant.  A useful equation for a surface greenhouse is:

@@ Line 50: / Line 50: @@
 For a greenhouse with a transmittance of 0,8, food production might be (.77 x 20.8 x .8)-6.1 = 6.7 g/m2/day
-For 260 days of production per year the yield would be 1.7 kg/m2 per year, or about 17 tonnes per hectare.
+For 260 days of production per year the yield would be 1.7 kg/m2 per year, or about 17 t/ha.
 ==Lighting levels==

← Older revision		Revision as of 16:24, 6 November 2020
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	Interior grow rooms use artificial light for plant production. This technology was developed for the production of Cannabis in closed environments but is applicable to all indoor grown plants. The most common power used for these installations is 300-600 W/m2, or about one quarter to one half the power of full sunlight.		Interior grow rooms use artificial light for plant production. This technology was developed for the production of Cannabis in closed environments but is applicable to all indoor grown plants. The most common power used for these installations is 300-600 W/m2, or about one quarter to one half the power of full sunlight.
		+
		+	Food production is a factor of the amount of illumination received by the plant. A useful equation for a surface greenhouse is:
		+
		+	Edible food=0.77 x PAR x T-6.1 (reference needed) where:
		+
		+	Edible food= Amount of edible plant mass produced (g/m2/day)
		+
		+	PAR= lighting level of photosynthetically active radiation. On Mars for natural lighting it is 20.8 (mol/m2/day).
		+
		+	T= transmittance of greenhouse surface.
		+
		+	For a greenhouse with a transmittance of 0,8, food production might be (.77 x 20.8 x .8)-6.1 = 6.7 g/m2/day
		+
		+	For 260 days of production per year the yield would be 1.7 kg/m2 per year, or about 17 tonnes per hectare.

	==Lighting levels==		==Lighting levels==

@@ Line 1: / Line 1: @@
-'''Lighting''' is vital for a colony. A colony might have a limited number of windows, so lighting would be required permanently. [[Plants]] in [[greenhouse|greenhouses]] might need to be lit artificially to supplement natural light. [[Rover|Rovers]] must have headlamps for driving at night or during [[dust storms]].
+'''Lighting''' is vital for a colony. A colony will have a limited number of windows, so artificial lighting may be required at all times. [[Plants]] in [[greenhouse|greenhouses]] will probably need to be lit artificially to supplement natural light. [[Rover|Rovers]] must have headlamps for driving at night or during [[dust storms]].
@@ Line 23: / Line 23: @@
 ===Health===
-The proper wavelengths of light are needed by [[human|humans]] to produce [[Vitamins|Vitamin D]].
+The proper wavelengths of light are needed by [[human|humans]] to produce [[Vitamins|Vitamin D]].  On Earth, about 15 minutes under the noon sun, 3 times a week, is enough to produce the required vitamin D.<ref>https://www.healthline.com/nutrition/vitamin-d-from-sun#time-of-day</ref>  On Mars, the exposure time would need to be longer.  Most type of glass screen ultraviolet light, so exposure under glass would not produce vitamin D.  Using ultraviolet light from artificial sources would product the same effect as the sun.
 Certain lights, emulating natural sunlight, are used to treat [[Seasonal affective disorder|Seasonal Affective Disorder]].
@@ Line 243: / Line 243: @@
 |}
-==Open Issues==
+==References==
 [[Category:Construction, Assembly, Maintenance]]
 <references />

@@ Line 7: / Line 7: @@
 Most light bulbs on Earth were incandescent until recently.  Due to their relatively low efficiency, incandescent lights are being phased out all over the world.<ref>https://en.wikipedia.org/wiki/Phase-out_of_incandescent_light_bulbs</ref>   In most commercial installation incandescent light bulbs have been replaced by fluorescents, that are themselves being replaced by LEDs.
-Fire and stars produce light via incandescence. In an incandescent light-bulb a metal filament (Usually [[tungsten]], the only metal that can withstand the temperatures) is heated to around 3000C. A [[glass]] bulb is fitted around the filament and the air evacuated or replaced by an inert gas, because the filament would otherwise oxidize and burn.
+Incandescence is a term usually reserved for a solid that emits light as it is heated. In an incandescent light-bulb a metal filament (Usually [[tungsten]], but carbon has also been used in the past,) is heated to around 3000C. A [[glass]] or quartz bulb is fitted around the filament and the air evacuated or replaced by an inert gas, because the filament would otherwise oxidize and burn.
 ===Fluorescent===
-===Halogen===
+===Light Emitting Diode (LED)===
+[[Light emitting diode|LED]] are [[energy]] efficient, and produce little heat compared to incandescent, fluorescent, and halogen lights.  They use the light emitted from a semi conductor in visible wavelengths and combine red green and blue components to produce white light.<ref>https://en.wikipedia.org/wiki/Light-emitting_diode</ref>
-===BioLEDS===
+LEDs in 2019 can produce about 220 lumens per watt, while incandescent light bulbs produce only about 14 lumens per watt and fluorescents 80 lumens per watt.<ref>https://greatercea.org/lightbulb-efficiency-comparison-chart/</ref>
 ==Human response to light==
@@ Line 245: / Line 247: @@
 *How much exposure time is needed for the skin to produce enough vitamin D?
 [[Category:Construction, Assembly, Maintenance]]
 <references />

@@ Line 5: / Line 5: @@
 ===Incandescent===
-Most lightbulbs on Earth were incandescent until recently. Fire and stars produce light via incandescence. In an incandescent light-bulb a metal filament (Usually [[tungsten]], the only metal that can withstand the temperatures) is heated to around 3000C. A [[glass]] bulb is fitted around the filament and the air evacuated or replaced by an inert gas, because the filament would otherwise oxidize and burn.  In most commercial installation incandescent light bulbs have been replaced by fluorescents, that are themselves being replaced by LEDs.  Incandescent lights are being phased out all over the world.<ref>https://en.wikipedia.org/wiki/Phase-out_of_incandescent_light_bulbs</ref>
+Most light bulbs on Earth were incandescent until recently.  Due to their relatively low efficiency, incandescent lights are being phased out all over the world.<ref>https://en.wikipedia.org/wiki/Phase-out_of_incandescent_light_bulbs</ref>   In most commercial installation incandescent light bulbs have been replaced by fluorescents, that are themselves being replaced by LEDs.
 ===Fluorescent===